Gunmen in Saudi Arabia have shot and killed five Westerners, including two Americans, two Britons, and an Australian.

All five worked for the energy company ABB-Lummus in the northwestern Saudi city of Yanbu. Three other company employees were wounded in the shooting.

The Saudi Interior Ministry says three of the four gunmen involved worked at the complex where the attack took place.

Following the shooting spree, the gunmen fled with Saudi police in pursuit through the city. Three of the gunmen were killed during the chase, while the fourth later died from his wounds. One Saudi security man also died in the clash.

Saudi Arabia's ambassador to Britain extended condolences to families of the shooting victims, calling the attack an "indiscriminate evil rampage."

The U.S. State Department renewed a warning this week that terrorists might try to attack American interests in the Middle East. The oil facility where Saturday's attack occurred is jointly owned by the Saudi company SABIC and the U.S. energy giant ExxonMobil.

Saudi Arabia has been battling a wave of Islamist militancy for the past year. An April 21 car bombing in Riyadh killed five people and wounded nearly 150 others.

More than 50 people were killed in suicide bombings in Riyadh last year.